Signaling system.



PATENTED NOV. 21, 1905.

2 SHEETS-SHEET l.

WITNESSEE.

PATENTED NOV. 21, 1905.

J. E. ALLISON.

SIGNALING SYSTEM.

APPLICATION FILED MAY4, 1904.

2 SHEETS-SHEET 2.

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UNITED STATES PATENT OFFICE.

JAMES E. ALLISON, OF ST. LOUIS, MISSOURI, ASSIGNOR TO GEORGE M. SEELEY, OF NEW YORK, N. Y.

SIGNALING SYSTEM.

Specification of Letters Patent.

Patented Nov.21, 1905,

Application filed May 4, 1904. Serial No. 206,366.

To aZZ whom it may concern:

Be it known that I, JAMES E. ALLISON, a citizen of the United States, residing at St. Louis, Missouri, have invented a certain new and useful Improvement in Signaling Systems, of which the following is afull, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, forming part of this specification, in which Figure 1 is a diagrammatic view illustrating the system, only one signaling-station being indicated. Fig. 2 is a side elevation of the switch. Fig. 3 is a top plan view of the same. Fig. 4. is a transverse sectional view through the contact-disk, ratchet, and pawl of said switch. Fig. 5 is a side elevation of the contact-carryingdisk of said switch, and Figs. 6 and 7 are detail views illustrating the switchactuating mechanism, and Fig.- 8 is a detail view illustrating the mechanism for sending the answering-back signals.

This invention relates to improvements in signaling systems, being more particularly an improvement upon the system forming the subject-matter of my application for patent, filed August 14, 1902, Serial No. 119,639.

Generally speaking, the system includes a home or central station and aplurality of signal or distant stations. Each signal-station is provided with a signal which is under the control of a switch, there being one switch for each Signal. At the home station is a sending instrument which controls the various before-mentioned switches. The switches are given step-by-step movement through the instru mentality of said sending mechanisms and are so set that each switch is brought into operative position at a time difierent from that at which any other of said switches is brought into operative position.

One object of the present invention is to provide means whereby the various beforementioned switches can be readily corrected or properly set with relation to each other.

A further object is to provide means whereby the signals at the various distant stations can be both thrown and reset from the home station.

A furtherobject is to provide means whereby the circuit which controls the magnet for operating each before-mentioned switch is positively made and broken for each step of such switch, and a further object is to provide an improved construction of Switch for use in systems of the character of the present.

To these ends and also to improve generally upon systems of the character indicated and upon the apparatus employed in such systems the invention consists in the various matters hereinafter described and claimed.

Referring now more particularly to the drawings. A represents the home station, and B indicates-one of the signal or distant stations. Each signal-station is provided with a suitable signal, such as the paddle C, the paddle being here shown as fixed to the rotatable shaft 1,-and this shaft being connected to a shaft 2 by means of a sprocketchain 3, which runs over sprocket-wheels 4 and 5 upon the respective said shafts. Upon the shaft'2 is a catch 6, adapted to be engaged by a movable latch or hook 7 which is formed upon one end of a pivoted armature. When the said latch engages the said catch, as shown by full lines in Fig. 1, the signal-paddle C is held in elevated or safety position, and when the said latch is thrown out of engaging position the weight of said signal-paddle causes the same to fall into operative or danger position, as shown by dotted lines in said figure.

At each signal-station is a solenoid D, whose helix 8 is in the line-circuit 9, this line-circuit being conveniently the trolley-circuit for op erating the cars upon the road, so that the solenoid is subjected to the influence of the heavy circuit from the dynamo, such circuit usually carrying about five hundred volts. The core 10 of said solenoid is connected to the said shaft 2, as by means of a chain 11, connected to a drum 12 upon said shaft. Normally the solenoid D is deenergized, and when the signal-paddle 0 falls the core 10 is partly withdrawn from the helix. When, however, the said solenoid is energized, the core 10 is drawn into the helix, and the shaft2is rocked to elevate the signal and cause the same to be locked in elevated position, all as will be readily apparent.

The latch-armature? is controlled by a magnet 13, which is in a circuit including a local battery 14:, said circuit also including a relatively fixed terminal 15 and a movable terminal 16, the latter being conveniently a pivoted armature. The said circuit also includes a second relatively fixed terminal 17 and a second movable terminal 18, with which said terminal 17 cooperates. As here shown, the terminal 18 is a conducting-strip in a rotatable disk 19, which is mounted upon a rotatable shaft 20, said shaft being included in the said circuit and having mounted thereon a ratchetdisk 21, with which a pawl 22 cooperates. It will now be apparent that if the disk 19 be moved to bring the terminal 18 into contact with the terminal 17 (the latter being a brush resting upon the periphery of said disk 19) and if the terminal 16 be brought into contact with the terminal the circuitincluding the local battery 14 will be closed, whereupon the magnet 13 will be energized, the latch-armature 17 will be thrown from detaining position, and the signal-paddle C will-be permitted to fall. The circuit 9 for controlling the solenoid D has separated terminals 23, with which a movable connector or bridge-piece 24 is adapted to contact, said bridge-piece being carried upon the core 25 of a solenoid E, w hose helix is marked26. This helix is in the circuit which includes said local battery 14, said terminals 15 and 16, and said terminal 18, said last-mentioned circuit also including a brush 27, which rests upon the periphery of said before-mentioned disk 19. The brush 27 is set one step behind the before-mentioned brush 17. In its rotation the said disk19 first brings the terminal 18 into contact with the terminal 17, whereupon the magnet 13 is energized and the signal-paddle falls, as heretofore explained. At its next step the said disk 19 carries the terminal18 out of contact with the terminal 17 and brings said terminal 18 into contact with the terminal 27, thus deenergizing the magnet 13 and energizing the helix 26, whereupon the bridge conductor 24 completes the circuit 9, which controls the solenoid D, and the signalpaddle is thus thrown into its normal safety position. A second local battery 28 is included in a circuit which includes a magnet 29, upon whose armature 30 is pivotally mounted the before-mentioned pawl 22, and the said lastmentioned circuit also includes a fixed terminal 31 and a movable terminal 32, the latter being in the present instance the armature of a polarized magnet F, one of the poles of said magnet being marked 33 and the other 34. Manifestly, when a current of one polarity is sent through said magnet F the pole 34 is energized and the armature-terminal 32 is thrown into contact with the terminal 31, whereupon the circuit including the magnet 29 is completed and the pawl 22 is actuated to move the disk 19 through one step. When a current of opposite polarity is sent through the magnet F, the pole 33 is energized and the armature 32 is moved to positively break said circuit which includes said magnet 29. The magnet F being energized the proper number of times, any desired disk 19 can be brought into circuit-forming position. A magnet 34 is adapted when energized to attract the -arma ture-terminal 16 and is included in a circuit with the battery 35 at the home station. As the circuit whichincludes the magnet 13 also includes the terminals 15 and 16 and the terminals 17 and 18 and as the circuit which includes the solenoid E also includes the terminals15 and 16 and the terminals 18 and 27, neither the magnet 13 nor the solenoid E can be operated until the proper circuit is closed at both breaks, so that, as is well understood, in order to operate a particular signal the two breaks in the local circuit controlling said signal must be simultaneouslyclosed.

At the home station are a sending instrument G, the before-mentioned battery 35, a battery 36, a battery 37, a magnet 38, its armature 39, which is a terminal adapted to oscillate between contact with either the fixed terminal 40 or the fixed terminal 41, a polechanger H, a magnet 42, its armature 43, which is connected to the movable terminals 44 and 45 of said pole-changer H, and a second manually-operable pole-changer I. The sending instrument comprises a fixed circular plate 46, which is provided with openings 47, the number of said openings corresponding to the number of teeth upon the before-mentioned ratchet-wheels 21. Said sendinginstrument also includes a rotatable shaft 48, upon which is mounted a toothed conducting-disk 49, the number of teeth in said disk corresponding to the number of teeth upon said ratchet-wheels 21, and also mounted upon said shaft and rotatable therewith is a contact-arm 50. Said shaft 48 is under the influence of a spring, and the disk 49 is normally held against movement by a suitable detent, such construction being well understood and being disclosed in my before-mentioned application, Serial No. 119,639. A plug 51 is adapted to be inserted in any of the openings 47 and to thus lie in the path of movement of said beforementioned contact-arm 50. Normally the shaft 48 is held by its before-mentioned detent to cause the disk 49 and contact-arm 50 to assume the zero position. (Indicated by full lines in Fig. 1.) When, however, the detent is removed, the spring causes said shaft 48 to rotate in a well-understood manner until said con tactarm 50 engages the pin 51, whereupon the said shaft and its disk and contact-arm are arrested. A brush 52, suitably supported upon the sending instrument, cooperates with the teeth of the disk 49. Said brush 52 is in connection with one pole of the before-mentioned battery 36, as by the wire 53, and the other pole of said battery is connected, as by the wire 54, with one pole of said magnet 42, the other pole of said magnet being connected, as by the wire 55, with the said toothed disk 49, which is made of coi'iductingmaterial. W' hen the disk 49 is at zero position, the brush 52 lies in a space between suitable teeth upon said disk. As the disk revolves, however, its teeth successively contact with said brush. Each time that a tooth makes such contact the circuit is completedthrough the magnet 42, and the movable terminals 44 and 45 of the pole-changer H are therefore thrown into position to contact, respectively,with the central terminal 56 and one side terminal 57 of said pole-changer, thus causing a current of one polarity to pass to the polarized magnet F. When the tooth which has been in contact with said brush 52 passes the same and the brush drops into the space between such tooth and the next following tooth, the magnet 42 is deenergized, whereupon the armature 43, under the influence of the spring 43, returns to normal position and the said terminals 44 and 45 of said pole-changer H contact, respec tively, with the side terminal 58 and the central terminal 56 of said pole-changer, whereupon a current of opposite polarity is sent through the said polarized magnet F. Thus as the toothed disk 49 rotates the magnet F is alternately oppositely energized, and the magnet 29 is therefore alternately energized and deenergized. The central terminal 56 of said pole-changer H is connected, as by the wire 59, with the before-mentioned armatureterminal 39, and the spring 60,controlling said armature-terminal, normally holds the latter in contact with the before-mentioned fixed terminal 40. This latter-mentioned terminal 40 is in connection with the said magnet F, so that as the said disk 49 rotates the said magnet is energized, as previously described. Preferably the terminal 40'is connected, as by the wire 61, with a brush 62 upon the sending instrument, and a second brush 63 upon said instrument is connected, as by the wire 64, with said magnet F. These brushes 62 and 63 are adapted to bear upon a circular conducting -strip 65 upon the said toothed disk 49, there being a break between the ends of said conducting-strip and this break being preferably filled by a block of insulation 66, upon which the said brushes 62 and 63 rest when the said toothed disk is in zero position. Thus when the said toothed disk is in such zero position the circuit through the said magnet F is broken. The terminals 44 and 45 of said pole-changer H are in connection with opposite poles of the before-mentioned battery 35, and the terminals 57 and 58 of said polechanger H are grounded, as through the wires 67 and 68, the said magnet F being also connected with the ground, as through the wire 69.

The terminal 41 is connected, as by the wires 70, 71, and 72, with one pole of the beforementioned magnet 34, the other pole of said magnet being connected with the ground, as by the wires 73, 74, and 75. The before-mentioned plug or pin 51 is in connection with one pole of the battery 37, as through the Wire 76, and the opposite pole of said battery is connected, as by means of the wire 77, with one pole of the before-mentioned magnet 38, the opposite pole of said magnet being connected to said contacting arm 50, as through the wire 78, whereby when the shaft 48 has rotated sufliciently and the contacting arm 50 comes to rest against said pin 51 said magnet 38 is energized and said armature-terminal 39 is thrown into contact with said fixed terminal 41, thus causing the current from the beforementioned battery 35 to be sent through the before-mentioned magnet 34, whereupon the terminal 16 is caused to contact with the terminal15. Thus rotation of said shaft 48 causes movement of both the toothed disk 49 and the contact-arm 50. Rotation of said toothed disk causes the terminal 18 to be brought into contact with the terminal 17, and when this occurs the contact-arm 5O rests against the plug 51, whereupon the terminal 16 is brought into contact with the terminal 15. Therefore rotation of said shaft 48 serves to complete the local circuit through the magnet 13 and its battery 14, whereupon the latch 7 is thrown and the signal-paddle C is permitted to fall.

To reset a signal-arm, it is only necessary to move the pin 51 into the next hole 47 of the sending instrument. This permitsthe toothed disk 49 and the contact-arm 50 of said sending instrument to advance one step, and such advance serves to carry the terminal 18 into contact with the brush 27 and also to again bring the terminal 16 into contact with the terminal 15. This completes the circuit through the local battery 14 and the solenoid E, whereupon the circuit through the solenoid D is completed and the signal-paddle C is restored to normal position in the manner previously explained.

Between the wires 70 and 71 is a sounder K, of any well-known or desired construction, adapted to operate upon the making and breaking of the circuit including the same, and makeand-break wheels 79 and 80 are connected, respectively, between the wires 74 and 75 and the wires 73 and 74. These make-and-break wheels are of the usual type found in such well-known devices as messenger-calls, the wire 75 terminating in a brush, which cooperates with the periphery of said wheel 79, and the wire 74 terminating in a brush which cooperates with the periphery of said wheel 80. Each make and break wheel is controlled by a spring, (81 and 82,) the respec tive springs being connected to crank-arms 83 and 84, as is common and well understood in connection with ordinary messenger-calls. Connected to the shaft 2 are oppositely-extending arms 85 and 86, and lever-arms 87 and 88 are loosely mounted upon the respective shafts which carry the said make-andbreak wheels 79 and 80, these lever-arms being connected to the respective arms 85 and 86 by links 89 and 90. Thus as the shaft 2 is rocked in one direction by the falling of the signal-paddle the lever-arm 87 is depressed in order to operate upon the crank-arm 84, and thus wind the spring which controls the make-and-break wheel 80, just as if said crankarm were moved by hand, as is common in messenger calls, while the lever-arm 88 moves away from the crank-arm 83 and permits the spring 81 (which has been previously wound) to cause the wheel 79 to rotate and to transmit a signal through the sounder K, the signal of course indicating that the signal-paddle C has dropped. When the signal-paddle is restored to normal position, the reverse rocking of said shaft 82 causes the lever-arm 88 to act upon the crank-arm 83, and thus rewind the spring controlling the make-andbreak disk 79 and also causes the lever-arm 87 to release the crank-arm 84, whereupon the spring 82 causes the disk 80 to rotate, and a signal is thus sent through the sounder K, the signal in this instance indicating that the signal-paddle has been restored.

What may be termed the mainswitch mechanism L (which includes the heretoforementioned disk 19)embodies a polarized magnet 91 and a cooperating armature-92, said parts being more clearly shown in Figs. 2 and 3, in which one pole of said magnet 91 is marked 93 and the other pole ismarked 94. When the armature-lever 92 (which forms a stop-lever) is attracted by the pole 93, said lever permits the disk 19 to rotate freely. When, however, said armature-lever is attracted by the pole 94, the end of said lever lies in the path of movement of a suitable stop-pin or other projection 95 upon the disk 19, so that the movement of said disk is limited. The armature-lever and stop-pin of each main switch are so set that when said pin and lever are in contact and the movement of the disk is thus arrested said disk is in its zero position. The said magnet 91 has one of its poles connected with the beforementioned wire 71 and its other pole connected with the before-mentioned wire 72, so that said magnet forms a part of the circuit including the beforementioned magnet 34. Under the ordinary circumstances the armature-lever 92 lies in position out of the path of movement of said stop-pin 95 and any impulse sent through the magnet 91 is of such polarity that the pole 93 is energized. Should any of the main switches L get out of step and it be desired to bring all of the switches into proper relationship with each other, it is only necessary to send an impulse of opposite polarity through the magnet 91 of each switch and to then permit the toothed disk-49 of the sending instrument to make a complete revolution. By sending an'impulse of opposite polarity through the magnet 91 of each main-switch mechanism the stoplever 92 of each of said main-switch mechanisms is attracted by the pole 94 and thrown into the path of movement of the stop-pin 95. The toothed disk 49 of the sending instrument G being then permitted to make a complete revolution, the disk 19 of each mainswitch mechanism is moved step by step in a manner which will be readily apparent, and

each disk is arrested in its zero position by means of its stop-pin 95 coming into engagement with the armature-lever 92. After the disks 19 of each switch mechanismL has thus been reset, a current of what may be termed normal polarity is sent through the magnet 91 of each said switch mechanism, whereupon the armature 92 of each such switch mechanism is withdrawn from the path of movement of the stop-pin 95. In order to control the polarity of the current through said magnets 91,the following-descri bed mechanism is provided: A pivoted arm 96 carries terminals 97 and 98, which are connected, as by means of the wires 99 and 100, with opposite poles of the before-mentioned battery 35. At one end of the throw of said pivoted arm 96 are terminals 101 and 102, and at the opposite end of said throw are terminals 103 and 104, the terminals 101 and 103 being connect ed, as by means of a wire 105, and the ter minals 102 and 104 being connected, as by means of a wire 106. If the pivoted arm 96 be at either end of its throw, the terminals 97 and 98 are in such connection with the terminals 101 and 102 or 103 and 104 that a current of such polarity as to energize the pole 93 of the magnet 91 can be transmitted to such magnet from the battery 35 when the remainder of the circuit including such magnet is closed. Intermediate the said fixed terminals at the ends of the throw of said pivoted lever 96 are contact-strips 107, 108,109, and 110, with which the before-mentioned terminals 97 and 98 contact as the pivoted arm 96 is thrown from one position to its opposite position, the said strips 107 and 108 being in the are described by the said terminal 97 and the said strips 109 and 110 being in the are described by the said terminal 98. The strip 110 is grounded, as through the wire 111, and the strip 109 is connected, as through the wire 112, with the before-mentioned wire 71, which leads to one pole of the magnet 91. The strip 108 is connected to the strip 110, as by the Wire 113, and the strip 107 is connected to the strip 109, as by the wire 114. It will therefore be apparent that as the pivoted arm 96 is swung to bring its carried terminals 97 and 98 upon the before-mentioned contactstrips the polarity of the current supplied to the magnet 91 is reversed, so that in order to reset the disks 19 of the various main switches L it is only necessary to throw the lever 96 into position to bring its carried terminals 97 and 98 into contact with the before-mentioned intermediate strips and to then permit the toothed disk 49 to rotate. After the toothed disk 49 has completed its rotation the leverarm 96 is thrown into one of its extreme positions and the initial direction of the current from the battery 35 is restored. The wire of the before-mentioned circuit 9 leads from the line and is connected to one of the before-mentioned terminals 23, the other of said termihals 23 being connected by thewire 116 with one pole of the helix 8, while the other pole of said helix is grounded, as through the wire 117. One pole of the battery 14 is connected by the wire 118 with one pole of the magnet 13, and the other pole of said magnet 13 is connected by the wire 119 with the brush17. The other pole of said battery 14 is connected by the wire 120 with the armature-terminal 16, and the cooperating terminal is connected by the wire 121 with the shaft 20, which is in connection with the terminal 18. The brush 27 is connected by the wire 122 with one pole of the helix 26, the other pole of said helix being connected by the wire 123 with the before-mentioned wire 118. One pole of the battery 28 is connected by the wire 124 with the terminal 31, and the other pole of said battery 28 is connected by the wire 125 with one pole of the magnet 29, the other pole of said magnet being connected by the wire 126 with the armature-terminal 32.

The wire 69 does not lead directly to ground from the magnet F of the first station, but is connected to the wire 64: at the next signalstation, so that the magnets F of the various stations are in a single circuit, the wire 69 from the last magnet in the series being grounded; also, the wire 7 5 does not lead directly to ground from the make-and-break wheel 7 9 of the first station, but is connected to the wire 71 of the second station, so that all of the magnets 91 and 34, together with the make-and-break wheels 79 and 80 of the various stations, are included in a single circuit, the wire 75 being grounded at the last station.

The construction of the main switch L is illustrated in Figs. 2 to 7. Referring now more particularly to said figures, 127 represents the base of theswitch, from which rises a supporting-arch 128, the before-mentioned lever 30 being pivotally supported upon said arch and being controlled by the before-mentioned magnets 29, suitably supported upon the base, the structure thus far described being substantially similar to the well-known telegraph-sounder. In standards 131 is journaled the before-mentioned shaft 20, upon which is sleeved the before-mentioned disk 19, this disk being adjustable circumferentially about the shaft and being fixed thereto in the present instance by means of the set-screw 132. The disk can therefore be placed in any desired relationship to the shaft circumferentially, .so that it can be set to cooperate with the mechanism for controlling any desired signal in the system. Fastened upon said shaft to rotate therewith are the before-mentioned ratchet-wheel 21 and a second ratchet-wheel- 133, the teeth of said wheels inclining in opposite directions and said wheels being conven: iently fastened together, as shown in Fig. 4. Loosely mounted upon said shaft 20 isabellcrank lever whose arm 13 1 has pivoted thereto the before-mentioned pawl 22, which cooperates with the ratchet-disk 21, while the arm 135 of said bell-crank lever is connected by a link 136 to said lever 30, so that reciprocation of said lever serves through said pawl to ad-' vance the ratchet-disk 21 in a manner which will be readily apparent. A suitable lockingpawl 137 also cooperates with said ratchetdisk to prevent backward movement of the same. J ournaled between suitable supports 138 is a rock-shaft 139, which carries a rock arm 140 in the form of a stop-pawl, cooperating with the ratchet-disk 133. A second rock-arm 14:1 upon said rock-shaft is connected by a link 142 with said lever 30, so that at each downward movement of said lever not only is the pawl 22 moved to advance the ratchet-disk 21 and its connected parts, including the disk 19, but the stop-pawl 14:0 is thrown in the path of movement of the appropriate tooth upon the disk 133 in order to pre vent excessive forward movement of the shaft 20. The shaft 20 is in electrical connection with the wire 121, as previously explained, and the conducting-strip 18, carried by said disk 19, engages said shaft 20 and extends to the periphery of said disk 19.

The before-mentioned brushes 17 and 27 are suitably supported upon the standard of the switch, as shown, and bear upon the periphery of said disk 19.

The polarized magnet 91, to ence has been previously made, upon the base 127 and cooperates with stop-lever 92, as previously explained.

After the sounder has operated and the despatcher is satisfied that the desired signal has been thrown the pin 51 is removed from the hole in the dial, whereupon the contact-arm and its contact-disk 4.9 are moved through the remainder of the revolution which has been partly made, the parts coming to rest at the proper time. During the revolution of the said shaft the teeth of the contact-disk have engaged the contact-finger 52, and at each engagement of said parts every switchdial 45 has been moved one step, so that when the contact-disk and the other parts of the sending instrument reach normal Zero position each switch-dial stands in its normal position, ready for a second operation.

lam aware that minor changes in the construction, arrangement, and combination of the several parts of my device can be made and substituted for those herein shown and described without in the least departing from the nature and principle of my invention.

Having thus described the invention, what is claimed as new, and desired to be secured by Letters Patent, is

1. In a system of the character indicated, a plurality of signals, a single sending instruwhich referis supported the ment, connections between the said sending instrument and the several signals whereby any one of the signals can be Separately operated by said instrument, and a connection between the instrument and the several signals whereby any single one of the signals can, through the instrumentality of said instrument be restored to normal position, said instrument being operable for operating all of said signals and for restoring all of them; substantially as described.

2. In a system of the character indicated, the combination with a signal, of an operative mechanism adapted in its operation to render said signal operative, asecond operative mechanism adapted in its operation to restore said signal to normal position, a circuit controlling said first-mentioned operative mechanism, a circuit controlling said second-mentioned oprative mechanism, a movable terminal included in each of said circuits, a terminal in each of said circuits with which said movable terminal is adapted to be brought into contact at different times, means for moving said movable terminal, a switch in each of said circuits, and means for operating said switch; substantially as described.

3. In a system of the character indicated, a signal, an operative mechanism adapted in its operation to render said signal operative, a second operative mechanism adapted in its operation to restore said signal to normal position, a circuit controlling said first-mentioned operative mechanism, a second circuit controlling said second mentioned operative mechanism, a movable terminal included in both said circuits, a terminal in each of said circuits with which said movable terminal is adapted to be brought into contact at different times, a switch in both said circuits, and a sendinginstrument including means whereby when said movable terminal is brought into contact with either of said fixed terminals said switch in said circuits is operated to render efl'ective the particular circuit with whose terminal said movable terminal is in contact; su bstantially as described.

4. In a system of the character indicated,-

the combination with a signal, of an operative mechanism through whose operation said signal is rendered operative, a second operative mechanism through whose operation said signal is restored to normal position, a circuit controlling said first mentioned operative mechanism, a second circuit controlling said second mentioned operative mechanism, a movable terminal in both said circuits, a terminal in each of said circuits and adapted to be contacted by said movable terminal at different times, an operative mechanism for giving said movable terminal a step-by-step movement, a circuit controlling said last-mentioned operative mechanism, a switch in both said first two mentioned circuits, an operative mechanism controlling said switch, and a sending instrument including means for control ling the said circuits controlling said last two mentioned operative mechanisms; su bstantially as described.

5. In a system of the character indicated, a signal, a source of energy, an operative mechanism through whose operation said signal is rendered operative, a second operative mechanism through whose operation said signal is restored to normal position, a circuit from said source of energy and including said firstmentioned operative mechanism, a second circuit from said source of energy and including said second-mentioned operative mechanism, a movable terminal included in both said circuits, a relatively fixed terminal in each of said circuits with which said latter-mentioned terminals said movable terminal is adapted to be broughtinto contact at different times,aswitch in both of said circuits, and means for controlling said movable terminal and said switch; substantially as described.

6. In a system of the character indicated, a signal, an operative mechanism controlling the same, a circuit including said operative mechanism, two switches in said circuit, a circuit controlling one of said switches, another circuit controlling the other thereof, terminals in each of said last-mentioned two circuits, and a movable terminal common to both said last-mentioned two circuits and adapted to contact with either of said last-mentioned two terminals for completing the particular circuit including the terminal with which said movable terminal is in contact; substantially as described.

7. In a system of the character indicated, a signal, an operative mechanism controlling the same, a circuit controlling said operative mechanism, two switches in said circuit, a source of energy, a terminal connected thereto, two terminals each of which is adapted to separately cooperate with said first-mentioned terminal, electrical connection between one of said two terminals and the operative mechanism for one of said switches, electrical connection between the other of said two terminals and the operative mechanism for the other of said switches, and means for causing electrical connection to be made between either of said two terminals and said terminal in connection with said source of energy; substantially as described.

8. In a system of the character indicated, a signal, an operative mechanism controlling the same, a circuit including said operative mechanism, two switches in said circuit, an operative mechanism for controlling each of said switches, a circuit including one of said switchcontrolling operative mechanisms,another circuit controlling the other of said switch-controlling operative mechanisms, a terminal in each of said last two mentioned circuits, a terminal common to both of said last two mentioned circuits and adapted to electrically contact with either of said first two mentioned terminals, means whereby said terminal common to both said last two mentioned circuits is normally in contact with one of its said 00- operating terminals, and a sending instrument including means for transmitting energy over said circuit whose terminal is normally in contact with said cooperating terminal and means whereby, at a desired time, said terminal common to both said switchcontrolling circuits is brought into electrical contact with the other of its said cooperating terminals for causing energy to be transmitted over the circuit including said lastmentioned terminal; substantially as described.

9. In a system of the character indicated, a signal, an operative mechanism controlling the same, a circuit including said operative mechanism, two switches in said circuit, a controlling mechanism for each of said switches, a circuit including one of said switch-controlling mechanisms, another circuit including the other of said switch-controlling mechanisms, a relatively fixed terminal in each of said last two mentioned circuits, a movable terminal common to both said last two mentioned circuits and movable between said first two mentioned terminals, an operative mechanism controlling said movable terminal, a circuit including said operative mechanism, means whereby said movable terminal is normall y in contact with one of its said cooperating terminals, a sending instrument including means for causing electrical impulses to be transmitted over the circuit including said last-mentioned relatively fixed terminal, said sending instrument also including terminals of said circuit which controls said beforementioned movable terminal, one of said terminals included in said sending instrument being movable with respect to the other thereof during the operation of said sending instrument; substantially as described.

10. In-a system of the character indicated, a signal, a circuit controlling the operation of said signal, two brushes in said circuit, a sending instrument, a conducting-strip in said sending instrument upon which said brushes are adapted to bear during the operation of said sending instrument, and a non-conducting portion between the end of said sendingstrip and adapted to receive said brushes when said sending instrument is inoperative; substantially as described.

11. In a system of the class described, a signal, means for rendering said signal operative, an operative mechanism for restoring said signal to normal position, a'main-line circuit, a circuit from said main-line circuit including said operative mechanism, and means for controlling said last-mentioned circuit comprising a switch in the last-mentioned circuit, and a pole-changer; substantially as described.

12. In a system of the character indicated, a signal, means for rendering said signal operative, an operative mechanism for restoring said signal to normal position, a main-line circuit, a circuit from said main-line circuit ineluding said operative mechanism, a switch in said last-mentioned circuit, a sending instrument, means whereby said sending instrument controls said means for rendering said signal operative, and means whereby said sending instrument also controls said switch;

substantially as described.

13. In a system of the character indicated, a signal, an operative mechanism for rendering said signal operative, asecond operative'mechanism for restoring said signal to normal position, a circuit including said first-mentioned ,operative mechanism, a terminal in said circuit, a second circuit including said secondmentioned operative mechanism, a switch in said second circuit, a switch-operating mechanism, a third circuit including said switchoperating mechanism, a terminal in said third circuit, a movable terminal common to both said first circuit and said third circuit and adapted to coact with either of said first two mentioned terminals, and means for operating said movable terminal; substantially as described.

14. In a system of the character indicated, a signal, an operative mechanism for rendering said signal operative, asecond operative mechanism for restoring said signal to normal position, a circuit including said first-mentioned operative mechanism, a terminal in said circuit, a second circuit including said secondmentioned operative mechanism, a switch in i said second circuit, a switch-operating mechanism for operating said switch, a third cir- .cuit including said switch-operating mechanism, aterminal in said third circuit, amovable terminal common to both said first circuit and said third circuit and adapted to cooperate with said first two mentioned terminals, a switch common to both said first circuit and said third circuit, and means for causing said movable terminal to contact with both said first two mentioned terminals at different times and for causing said last-mentioned switch to be operated simultaneously with the contact of said movable terminal with either of said first two mentioned terminals; substantially as described.

15. In a system of the character indicated, a signal, means for rendering said signal operative, means for restoring said signal to normal position, means for automatically causing a signal to be transmitted when said firstmentioned signal is rendered operative, and means for causing a signal to be transmitted when said first-mentioned signal is restored; substantially as described.

16. In a system of the character indicated, a signal, means for causing said signal to be rendered operative, means for causing said signal to be restored, two signal-sending mechanisms, a mechanism under the control of said first-mentioned signal for operating said signal-sending mechanisms, and means whereby when said first-mentioned signal is rendered operative one of said signal-sending mechanisms is permitted to operate and the other of said signal-sending mechanisms is placed in operative condition, and means whereby when said first-mentioned signal is restored said other of said signal-sending mechanisms is permitted to operate and said first separatelymentioned signal-sending mechanism is rendered operative, substantially as described.

17. In a system of the character indicated, a signal, a circuit controlling said signal and including a switch, step-by-step mechanism for operating said switch, a circuit including said switch-operating mechanism, a second switch included in said last-mentioned circuit, and means whereby, for each step of movement of said first-mentioned switch, said last-mentioned switch is electrically thrown into circuit-forming position and electrically thrown into circuit-breaking position; substantially as described.

18. In a system of the character indicated, a signal, a circuit controlling. the same and including a step-by-step switch, switch-operating mechanism, a circuit controlling said switch-operating mechanism and including a second switch, a polarized magnet controlling the movable member of said second switch, a sending instrument, and means controlled by said sending instrument for alternately energizing the opposite poles of said polarized magnet; substantially as described.

19. In a system of the character indicated, a signal, a circuit controlling the operation of said signal and including astep-by-step switch, switchoperating mechanism, a circuit controlling said switch-operating mechanism and including a second switch, a polarized magnet controlling the movable member of said second switch, a circuit including said polarized magnet, a pole-changer in said circuit, a sending instrument, and means whereby said sending instrument in its operation causes operation of said pole-changer; substantially as described.

20. In a system of the character indicated, a plurality of signals, a step-by-step switch for each of said signals, a sending instrument controlling all of said switches, and means whereby all of said switches can be corrected with respect to each other; substantially as described.

21. In a system of the character indicated, a plurality of signals, a step-by-step switch controlling each of said signals, a stop member upon each of said switches, a cooperating stop member for each of said switches, a central station, means for operating each of said switches from said central station, means for normally holding each of said cooperating stop members in inoperative position, and means whereby each of said cooperating stop members can be thrown into stopping position from said central station; substantially as described.

22. In a system of the character indicated, a plurality of signals, a step-by-step switch controlling each of said signals, a stop member upon each of said switches, a cooperating stop member for each of said switches, a polarized magnet controlling each of said cooperating stop members, a circuit including said polarized magnets, a pole-changer in said circuit, and means for operating said several switches; substantially as described.

23. In a system of the character indicated, the combination with a switch including a rotatable disk, a conductor carried by said disk, a terminal cooperating with said conductor, and means for actuating said disk by a stepby-step movement, of a stop member connected to said disk, 2. cooperating stop member, and means for throwing said cooperating stop member into and out of the path of movement of said first-mentioned stop member; substantially as described.

24. In a switch of the character indicated, a rotatable disk, a conductor carried by said disk, a terminal cooperating with said conductor, and means for moving said disk by a stepby-step movement, of a stop'member eon nect ed to said disk, a polarized magnet, and a stoplever pivotally supported between the poles of said magnet; substantially as described.

25. In a switch of the character indicated, a rotatable shaft, a disk fastened thereto, a conductor carried by said disk, a terminal cooperating with said conductor, a ratchet-disk fastened to said shaft, an arm loosely mounted uponsaid shaft, a pawl carried by said arm and cooperating with said disk, a lever, and operative connection between said lever and said pawl-carrying arm; substantially as described.

26. In'a switch of the character indicated, a

rotatable shaft, adisk fastened upon said shaft, a contact member carried by said disk, a terminal cooperating with said contact member, a ratchet-disk fastened upon said shaft, a bellerank lever loosely mounted upon said shaft, a pawl upon one arm of said bell-crank lever and cooperating with said ratchet-disk, a lever and a link connecting said lever and the other arm of said bell-crank lever; substan tially as described.

27. In a switch of the character indicated, a rotatable shaft, a disk fastened upon said shaft, a conductor carried by said disk, a terminal cooperating with said conductor, a ratchetdisk fastened upon said shaft, an operatinglever, a rock-shaft, a pawl upon said rock- In testimony whereof I hereunto afiix my signature, in the presence of two witnesses, 1 this 25th day of April, 1904.

JAMES E. ALLISON.

Witnesses: GALEs P. MOORE GEORGE BAKEWELL. 

